Muffler



W. B. M LEOD MUFFLER 2 Sheets-Sheet 1 Filed Nov. 24, 1951 a y M WM; 5% W Gm M My Y April 13, 1954 w. B. MOLEOD MUFFLER 2 Sheets-Sheet 2 Filed Nov. 24, 1951 Patented Apr. 13, 1954 UNITED STATES PATEIIT OFFICE MUFFLER William B. McLeod, Burban-k,,. Calif.

Application November 24, 1951, Seri'aI'No. 258,010

1 Claim. 1

This invention relates to improvements in muillers for mufiling or silencing the exhaust from internal combustion engines.

A primary object of the invention is to providean improved mufiier which is extremely simple" in design, enabling the parts to be easilyma-nufa-ctured and assembled and which is high- 1y efli'cient in its operation, providing for adequate expansion of gases and a ready heat-transference to the ambient atmosphere.

With theforegoing and other objects in view, which will be made manifest in the following detailed description and specifically pointed out in the appended claims, reference i had to the accompanying drawings for an illustrative embodiment of theinvention, wherein Figure 1 is a longitudinal horizontal section through one form of mufiler embodying the present invention;

Fig. 2' is a vertical section taken substantially upon the line 2-4 upon Fig. 1; v

Fig. 3 is a vertical section through another form of muffler embodying the present invention;

Fig. 4 is a Vertical section taken substantially upon the line 4-4 upon Fig. 3. in the direction indicated;

Fig. 5 is a longitudinal section through still another form of muffier embodying the present invention; and

Fig. 6' is a vertical section taken substantially upon the line 66 upon Fig. 5 in the direction indicated;

Referring to the accompanying drawings wherein similar reference characters designate similar parts throughout, [0 indicates an inlet pipe adapted to be connected to the exhaust pipe from an internal combustion engine. This pipe extends into a shell or outer housing through an end plate II thereof. The outlet or tail pipe from the muffler is indicated at I2 which extends outwardly through an end plate l3. The end plates I! and I3 may be welded to the pipes l0 and I2, respectively. They are connected to each other by an outer shell of sheet metal indicated at 14, the end edges of which may be welded or crimped onto the end plates as indicated at l5.

Within the outer housing the portions of the pipes 10 and II are perforated with perforations indicated at l6 and I1, respectively, and in the 1 preferred form of construction the diameter of the inlet pipe ID is slightly larger than that of the outlet or tail pipe l2 although this relative size is not usually important insofar as the present invention is concerned. The two pipes I0 2. and I2 in the construction shown in Fig. 1 are coaxially arranged and are in direct alignment with each other. Their inner ends, however, are spaced from each other and are surrounded by a sleeve l8 having an internal diameter some what larger than the external diameters of the pipes l0 and 12. This sleeve is divided centrally by means of transverse imperiorate partition IS. The end edges of the sleeve are divided or slitted to define fingers 20 that can be bent inwardly to frictionally engage the inner ends of the pipes l0 and 12. This frictional engagement in some forms of muffler may be sufficient to hold the sleeve H3 in position. However, in other instances it may bedesirableto weld the ends of the fingersto their'respective pipes.

In this formof construction as' the exhaust gases from the internal combustion engine enter the pipe In some of these gases may expand or find egress through the perforations IS. A substantial portion and probably a major portion of the gases issue from the inner end of the pipe and encounter the i'rnperforate partition l9. These gases flow between the interior of the sleeve ['8' and the exterior of the pipe l0 between the fingers 2B- and enter the space 2| within the outer housing which forms a relatively large expansi'on chamber in which the gases can expand and heat may be transferred through the sheet metal shell M to the surrounding atmosphere. The expanded and cooled gases reenter the sleeve I 8 between the sleeve and the outlet pipe [2, such gases flowing between the fingers 20. Some of the gases may enter the pipe 12 through the perr forations I! and thus pass out of the mufiier.

It will be appreciated from the above-described construction that the parts of the improved muffier may be very easily manufactured and assembled together and provision is made for releasing the gases into a relatively large expansion chamber near the forward end of the mufiier and ultimately conducting these expanded gases to the tail pipe.

The construction disclosed in Fig. 1 may be advantageously employed where the inlet pipe and the outlet pipe l2 can be in direct alignment. In some mufiler constructions, however, it is necessary that the inlet pipe and the tail pipe bear an offset relation to each other. Fig. 3 discloses such a construction wherein the inlet pipe is indicated at 25 extending into the outer housing through an end plate 26. In a similar manner, the outlet pipe 2'! leads out of the mufller through an end plate 28. The two pipes 25 and 21 bear an onset relationship to each other although they are parallel. In this construction, the inner end of the inlet pipe 25 is surrounded by a sleeve 29 in spaced relation to the exterior of the inlet pipe. Fingers 30 may be utilized to hold the sleeve in spaced relation thereto. The sleeve is closed at its remote end by an imperforate wall 3| corresponding in position and in function to the partition l9. In a similar manner, the inner end of the outlet pipe 21 is provided with a sleeve 32 closed at its inner end by an imperfora-te wall 33 and having fingers 34. The two pipes 25 and 21 may be perforated with perforations 35 and 36 within the outer housing that is defined by the shell 31 that connects the end plates. The exteriors of the two sleeves 29 and 32 may be rigidly connected together, such as by straps 38 welded thereto. In this form of construction, exhaust gases entering the inlet pipe 25 may find egress therefrom through the perforations 35 and after encountering the wall 3| they are caused to flow in a reverse direction between the sleeve 29 and the inlet pipe and between the fingers 30. These gases may expand within the outer housing and lose a substantial portion of their heat through the walls of the outer housing. The expanded gases enter the tail pipe 21 through the perforations 3B and by flowing between the sleeve 32 and the inner end of the tail pipe. This form of construction functions in very much the same manner as that previously described, but is so designed that an offset inlet and outlet pipe may be employed where such a construction is required.

In a construction, as shown in Figs. and 6, the inlet pipe is illustrated at 40 and the outlet pipe at 4|. These pipes are perforated with perforations 42 and 43 and are arranged in alignment with each other. A sleeve 44 surrounds the adjacent ends of the two pipes and is divided by an imperforate partition 45. This sleeve may be held in concentric relationship with respect to the pipes by means of the fingers 46. However, in this form of construction which has been designed for heavy duty, plates 41 and 48 are telescoped over the inlet pipe 40 and secured thereto such as by welding. A similar plate 49 may be telescoped over the outlet pipe 4|. Angle irons 50 are positioned against the corners of these plates and are welded thereto. These angle irons extend from end to end of the outer housing 5| and have their ends secured to the end plates thereof. The central portions of the angle irons are arranged to be in engagement with the sleeve 44 and are welded thereto. In thi manner, the angle irons extending from end to end of the outer housing cooperate to sturdily support the sleeve 44 centrally of the housing and in concentric relationship to the inner ends of the two pipes 40 and 4|. They also cooperate through the plates 41, 48, and 49 to firmly support the pipes 40 and 4| Within the outer housing. The operation of the form of construction disclosed in Figs. 5 and 6 is substantially the same as that previously described.

From the above-described construction it will be appreciated that the improved mufiler can be easily and economically manufactured and have its parts readily assembled together. In operation, gases discharged into the mufller are given an opportunity to expand in a relatively large expansion chamber and are ultimately collected and directed into the tail pipe.

Various changes may be made in the details of construction without departing from the spirit and scope of the invention as defined by the appended claim.

I claim:

A muffler comprising an outer elongated housing, end plates having openings therein covering each end of the housing, aligned inlet and outlet pipes extending into the housing through the openings in said end plates, the interior ends of said pipes being in a spaced-apart relationship, a sleeve about the inner adjacent ends of said pipes, a partition in said sleeve between the inner ends of said pipes, elongated angle irons within said housing and secured to said sleeve, 2. number of plates telescoped onto the pipes and secured to said angle irons, said angle irons being supported within said housing by said end plates.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,044,397 Knopp Nov. 12, 1912 1,553,264 Reasonover Sept. 8, 1925 1,938,973 Oldberg Dec. 12, 1933 2,109,220 Noblitt et a1 Feb. 22, 1938 2,544,284 Stephens et a1 Mar. 6,1951

FOREIGN PATENTS Number Country Date 593,282 Great Britain Oct. 13, 1947 350,031 Italy July 3, 1937 

